Rotating load platform for lift trucks



Sept. 28, 1954 QUAYLE ROTATING LOAD PLATFORM FOR LIFT TRUCKS 4Sheets-Sheet 1 Filed March 11, 1949 #6 ATTORNEY Sept. 28, 1954 G. F.QUAYLE ROTATING LOAD PLATFORM FOR LIFT TRUCKS Filed March 11, 1949 4Sheets-Sheet 2 ATTORNEY Sept. 28, 1954 QUAYLE 2,690,272

ROTATING LOAD PLATFORM'FOR LIFT TRUCKS Filed March 11, 1949 4Sheets-Sheet 3 'ATTORNEY p 28, 1954 F. QUAYLE 2,690,272

ROTATING LOAD PLATFORM FOR LIFT TRUCKS Filed Sarah 11, 1949 4Sheets-Sheet 4 INVENTOR W E W ATTORNEY Patented Sept. 28, 1954 ROTATINGLOAD PLATFORM FOR LIFT TRUCKS George F. Quayle, Philadelphia, Pa,assignor to The Yale & Towne Manufacturing Company, Stamford, Conn., acorporation of Connecticut Application March 11, 1949, Serial No. 80,891

Claims.

1 This invention relates to an industrial truck of the type in which aload carrier is moved vertically on uprights or the like, and is adaptedto be rotated whereby to dump a load carried thereby. There are numerousstructures of the particular class in the prior art, and in general theload car-- rier rotating means take the form of a hydraulic or electricmotor in operating relation to a part of the carrier.

It is apparent that when a hydraulic motor is utilized in an arrangementof the particular class, hydraulic l nes must extend between the motorand a part of the main frame, with the lines flexing so that the motortogether with the carrier may move vertically. Obviously, an arrangementof this type is objectionable because it is dimcult to mount thehydraulic lines so that they will not be damaged during the verticalmovement of the carrier, and so that they will not interfere with theoperation of the truck.

Where an electric motor is used, it is obvious that in addition to theexpense of supplying an electric motonit is necessary to run electricwires to the motor from the main frame of the truck to supply the power,and that these lines must, of course, allow for a vertical movement ofthe load carrier relatively to the truck.

Some prior art trucks utilize an electric motor and a hydraulic motorboth mounted on the moving carriage, with the electric motor operating apump for generating the hydraulic pressure used by the hydraulic motor.This arrangement is used where it is desired to have the advantages of ahydraulic operation of the load without requiring long hydraulic linesextending to the main frame of the truck.

As my invention, I have conceived a structure whereby it is possible torotate what I call a load carrier through means that are operativeincidental to the normal linear movement of the load carrier onthe'usual uprights or the like of a truck of the particular class. Thus,it is a feature of my invention that the mere linear movement of theload carrier relatively to the main frame of the truck will effect theactuation of means for rotating the load carrier.

More particularly, a feature of my invention resides in the utilizationof a flexible member, preferably a sprocket chain, reeved over a seriesof rotating wheels, which will be sprockets where a chain is used, therebeing at least one sprocket for rotating the load carrier. So long asthe rotating load carrier is predisposed against rotation, its linearmovement will carry the flexible member with it, and this flexiblemember will rotate certain of the wheels over which it is reeved. Whenthe flexible member is held against movement relatively to certain ofthe wheels over which it is reeved, and the load carrier moves linearlyrelatively to the main frame, it is obvious that the carrier rotatingwheel or sprocket must then be rotated. This rotation is effective torotate the load carrier.

As a further particular feature of my invention, means are provided forlocking the flexible member, or the sprocket chain where that is used,against movement. As a more particular feature of this part of theinvention, the locking means are in the form of a brake for one of thewheels. By applying this brake with varying degrees of pressure, thespeed of rotation of the load carrier is readily and well controlled, aswill be quite apparent.

As a further feature of my invention, I utilize novel means, preferablyguide rollers, for yieldingly maintaining the load carrier againstrotation during normal vertical movement thereof.

I have thus outlined rather broadly the more important features of myinvention in order that the detailed description thereof that followsmay be better understood, and in order that my contribution to the artmay be better appreciaed. There are, of course, additional features ofmy invention that will be described hereinafter and which will form thesubject of the claims ap pended hereto. Those skilled in the art willappreciate that the conception on which my disclosure is based mayreadily be utilized as a basis for the designing of other structures forcarrying out the several purposes of my invention. It is important,therefore, that the claims to be granted me shall be of sufficientbreadth to prevent the appropriation of my invention :by those skilledin the art.

Referring now to the drawings, Fig. 1 is a side elevation of a truckutilizing my invention. Fig. 2 is an end elevation of the truck ofFig. 1. Figs. 3 and 4 are further end elevations showing theloadcarriage and load carrier in different operating positions. Fig. 5is an enlarged side elevation and section of a part of the invention.Fig. 6 is an enlarged elevation of the load carriage with the loadcarrier removed. Fig. 7 is a section taken along lines l-'l of Fig. 5.Fig. 8 is a section taken along lines 8-8 of Fig. 6. Figs. 9 and 10 aresections taken respectively along lines 99 andlii-lt of Fig. 2. Fig. 11is a section taken along lines 5 ll i of Fig. 8. Fig. 12 is a sectiontaken along lines l2-l2 of Fig. 6.

Referring now more particularly to the drawings, my invention is shownapplied to what is known as a motorized hand truck. Obviously, it can beapplied to any type of industrial truck having a load carriage movableon a part of the main frame. In the particular truck shown by me, themain frame is designated by reference numeral Ill and is shown supportedon wheels I! and If, the wheel l2 being a traction and steering wheel,and adapted for steering by a handle l3, the end of which containscontrol switches M for a traction motor connected to driving wheels l2.A battery compartment 55 supplies the power for the traction motor andalso for the motor that drives the usual pump for supplying fluid underpressure to a standard lifting ram l6. Lifting ram [5 is of that typewell known in the art adapted to actuate a chain H through sprockets [8,one end of the chain being secured at I 9 to the main frame of the truckwhile the other end of the chain is secured at 26 to an elevatingcarriage 2 I.

Elevating carriage 2! is equipped with the usual upper and lower rollers22 cooperating with vertical uprights 23 forming part of the main frameof the truck. In some cases, the uprights 23 are adapted for pivotalmovement relatively to the main frame as about the axles 24 of thewheels H, and such movement is generally imparted by a hydraulic orelectric motor through suitable mechanism. Insofar as my invention isconcerned, it is merely necessary to know that the uprights 23 are partof the main frame of the truck and that the lifting carriage 2! isadapted for upward and downward vertical movement thereon, this movementbeing contributed by hydraulic ram I8 through the chains ll. Themechanism I have thus far described is old and well known in the art,and per se is not the invention of this application. The inventionforming the subject matter of this application will now be set forth indetail.

Referring now particularly to Fig. 8, load carriage 2! is shown formedwith a forward plate 25 to which is welded bearing support 26. Thisbearing support 2% has mounted thereon a spherangular outer race 2'!supporting ball bearings 28 that operate relatively to an inner race 29.Mounted for rotation with the inner race is a relatively heavy stubshaft Bil that is welded to form an integral part of the plate 3! ofload carrier 32. A cover plate 33 is bolted to the stub shaft 3a tocover one end of the ball bearing mounting for the said stub shaft 36.The other end of the mounting is covered by a part of a sprocket wheel35 that is keyed or otherwise fixed to the stub shaft as. In this way,the load carrier 32 is adapted for rotation with the stub shaft 38 andsprocket 34 relatively to the load carriage 2 l It will be appreciatedthat the spherangular outer race 27 of the ball bearing mounting forstub shaft 38 allows slight angular swinging movement of the loadcarrier 32 relatively to its axis of rotation, this movement beingrelied upon as will now be set forth. Thus, as is well shown in Figs. 8,9, and 10, a pair of brackets 35 support a stabilizing roller 3trelatively to plate 25 of load carriage 2i. Similarly, a second pair ofbrackets 37 support a stabilizing roller 38. However, roller 38 extendsoutwardly relatively to the plate 25 beyond roller 33. Therefore, thetwo rollers will maintain the plate 3| of load carrier 32 in a planedetermined by the peripheries of the said rollers, the necessarymovement of the plate 3| for alignment with this plane being allowed bythe nature 4 of the spherical surface ball bearing mounting of the shaft38.

Plate EE is equipped with a groove 39, and as soon as this groove 39moves into alignment with the roller :16, the roller moves into the saidgroove while the plate 3! swings into the particular plane shown in Fig.8. It is in this plane that the plate 3| is intended to lie in thenormal position of the load carrier 32. Therefore, any rotation of theload carrier 32 from its position if Fig. 8 must tend to move the entireload carrier out of the plane in which it lies in Fig. 8 in order tobring the groove 39 away from under roller 38. Because of the particulararrangement, the load carrier 32 is predisposed to remain in the planeshown in Fig. 8 relatively to the load carriage 2i and it followstherefore, that it takes rather considerable effort to move the loadcarrier out of the said plane through rotation thereof on the axis ofthe stub shaft 2-38. It can, therefore, be said that the stabilizingrollers 35 and 3t function not only to stabilize the load carrier, butalso to maintain it yieldingly against rotation relatively to the loadcarriage 2 l.

The plate 3! of the load carrier 32 carries an upper integral ledge Mland a similar lower int gral ledge ll. These ledges are utilized formounting any type of load contacting mechanism, the general type nowpreferred in the art being a fork. As is probably best illustrated inFigs. 1, 2, 8, and 11, I use a right fork Q2 and a left fork 43. Eachfork has a vertical arm M and a horizontal tine 45. Each fork hasfurther a laterally and horizontally extending bracket 45 bored for aplunger 47 urged downwardly by a spring 48 and adapted to be liftedagainst the pressure of the spring by a handle t9. Ledge 4! is formedwith two series of bores 5%, there being one series for the right handfork 52 and another series for the left hand fork it. When it is desiredto apply a fork to the carrier 32, it is merely necessary to slip theupper end of the arm i l of the fork under the hook film of the upperledge 4'!) while the horizontal bracket d6 rests on the lower ledge H.The plunger 47 of each fork will enter a particular one of the holes 5%of the lower ledge M depending on the horizontal spacing of the forks.Because of this construction of the parts, it is possible to adjust theforks toward and away from one another for cooperating with loads ofdifferent width.

The sprocket wheel 34, adapted for integral rotation with the stub shaft34 and load carrier plate 3i, coacts with a sprocket chain 5i that isquite well shown in the several figures of the drawings. This chainmoves over a series of sprockets, there being four of these sprockets inthe preferred form of my invention. Two of the sprockets are designatedby reference numerals {i2 and 53, these sprockets being mounted for freerotation on the plate 25 of load carriage 2!. The mounting means may beof any type, but in Fig. 12 I demonstrate how I prefer to mount the saidsprockets, the particular mounting of Fig. 12 being that of sprocket 52.

The sprocket chain is further reeved over a sprocket 52 that is carriedby an arm 55, this arm 55 being secured through a bolt 56 to one of theuprights 23. Arm 55 is readily adjustable about the axis of bolt 5t bymeans of an adjusting screw 51 suitably mounted as well illustrated on abracket 58 fixed to one of the uprights 23. The particular mounting ofthe sprocket at is for the purpose of adjusting the position of thesprocket to compensate for variations in length of chain 5|.

The fourth sprocket is designated by reference numeral 59 and itsmounting is best illustrated in Figs. 1, 5, and 12. Thus, sprocket 59 iscarried by a shaft 60 and rotates on bearing sleeves Bl carried by asleeve 62 welded to one of the uprights 23 through plates 23a. The leftend of the shaft 69, as viewed in Figs. 5 and -6, carries a brake drum63 with which coacts a brake band 55. One end of the brake band 64 issecured to a lever 65 pivoted at 66 to the left upright 23 while theother end of the brake band 54 is secured through a pivot shaft 61 to apart 68 integral with a rod 69. a lower surface of aguide bracket H forthe rod 89 and the part 68 for normally urging the rod 59 downwardly inthe several figures of the drawmgs.

A clevis 69a, integral with the upper end of the rod 69, is pivoted atT2 to a cylindrical part '53 (Figs. 6 and 7) mounted for rotationthrough a short shaft 14 relatively to spaced brackets f5, 15 welded tothe left upright 25. Formed integrally, as by welding, with the part isis an operating lever 1'1; Obviously, the spring ill wili normally holdthe rod 69 so that the brake band 64 will be loose relatively to brakedrum 53. When the lever 71 is moved to rotate part 13 on its shaft M,the rod 69 will be moved vertically against the pressure of spring 7E!and the brake band will be applied forcefully to the brake drum 63. Thiswill naturally hold the shaft til and the sprocket 59 against rotation.

Let us consider now that the load carrier is in its position of Fig. 8relatively to the load A spring 10 operates between carriage 2| and thatthe load carriage 2! is in its position of Fig. 2. If hydraulic fluid isnow supplied to the ram I6, it is obvious that the load carrier willmove with the load carriage to the position of Fig. 3 from the positionof Fig. 2. If the forks 42, 43 carry a bin B, that bin will be elevatedto the position of Fig. 3, the tines of the forks coacting with flangesof the channels 88 for lifting the said bin. During this linear movementof the load carriage relatively to the uprights 23, the load carrier hasbeen predisposed by rollers 36, 38 against rotation relatively to theload carriage, and the brake band 65 has not been applied against thebrake drum 63. Therefore, the sprocketchain 5i was moved with thesprocket 34, the said chain rotating the guiding and controllingsprockets 54 and 59.

Let us now assume that with the bin in the position of Fig. 3, itbecomes desirable to rotate the bin whereby to empty it of its load. Theoperator will then move lever 11 to rotate the part 13 about its shaft14. This will move rod 69 to brake the drum 63 and lock the shaft es andsprocket 59 against rotation. At the same time, the operator willcontinue the movement of the load carriage vertically upwardly from theposition of Fig. 3 to the position of Fig. 4. The extent of thismovement is well measured in Figs. 3 and 4 by comparing the verticalpositions of the sprocket 34 and shaftfill in the two figures. Duringthis vertical movement of the load carriage, since the chain 5| cannotmove, it is obvious that the sprocket 34 must rotate. This rotation ofthe sprocket will'naturally effect rotation of the load carrier 32, thefirst rotation of the load carrier being against the resistance ofroller 38. Therefore, during the vertical move-- ment of the loadcarriage from the position of Fig. 3 to the position of Fig. 4, the loadcarrier 6 will rotate relatively thereto so as to turn the bin B upsidedown andempty it of its con tents. Now, by lowering the load carriage,the bin will be rotated back to the position of Fig. 3. Thereafter thebrake band can be released to allow free rotation of sprocket 59 andfree movement of chain 5| so that the load carriage may be lowered withthe load carrier and the bin B from the position of Fig. 3 back to theposition of Fig. 2.

It is now obvious that merely through the utilization of a series ofsprockets and a sprocket chain, I can readily rotate the load carrier ofmy truck through the mere operation of the usual load carriage liftingmechanism. I am therefore able to dispense with the complex and costlyload carrier rotating means of the prior art. Moreover, by the carefulapplication of my braking mechanism, 1 can very readily control thespeed of rotation of the load carrier in a manner that is extremelydesirable. I believe that the con" siderable novelty of my invention andthe contribution it makes to the art will now be unden stood.

I new claim:

1. in a truck of the class described, a main frame, a load carrier,means mounting said load carrier for linear movement on said main frame.

means mounting said load carrier for rotary movement relatively to saidmain frame, means actuated incidental to the linear movement of saidload carrier relatively to said main frame for rotating said loadcarrier relatively to said main frame, rollers bearing between said loadcarrier and its mounting means for stabilizing said load carrier, and adepression into which one of said rollers enters in a particular rotatedposition of said carrier to hold said carrier yieldingly in saidposition.

2. In a truck of the class described, a main frame, a load carrier,means mounting said load carrier for linear movement on said main frame,spherical surface bearing means mounting said load carrier for rotarymovement relatively to said mainframe, means actuated incidental to thelinear movement of said load carrier relatively to said main frame forrotating said load carrier relatively to said main frame on said bearingmeans, rollers for stabilizing said load carrier, and a depression insaid load carrier into which one of said rollers enters in a particularrotated position of said carrier whereby with said other roller to movesaid carrier on its bearing means thereafter to hold said carrieryieldingly in said particular rotated position.

3. In a truck of the class described, a main frame, a load carrier,means mounting said load carrier for linear movement on said main frame,means mounting said lead carrier for rotary movement relatively to saidmain frame, a series of rotating wheels mounted on said main frame, anactuator wheel fixed to said carrier with its axis coinciding with theaxis of rotation of said carrier for effecting rotation of said carrieron its mounting means, a flexible member reeved over all of said wheels,the linear motion of said carrier and said actuator wheel acting to movesaid flexible member therewith relatively to the wheels when saidflexible member is free to move with said load carrier and said actuatorwheel is predisposed against rotation, and means whereby said flexiblemember is held against motion as said carrier moves linearly whereuponsaid flexible member in turn rotates said actuator wheel to rotate saidcarrier relatively to its mounting means as said load carrier moveslinearly of said main frame.

4. In a truck of the class described, a main frame, a load carrier,means mounting said load carrier for linear movement on said main frame,means mounting said load carrier for rotary movement relatively to saidmain frame, rotating sprockets mounted on said. main frame, an actuatorsprocket fixed to said carrier with its axis coinciding with the axis ofrotation of said carrier for efiecting rotation of said carrier on itsmounting means, a chain reeved over all of said sprockets, the linearmotion of said carrier and said actuator sprocket acting to move saidchain therewith relatively to the sprockets on said main frame when saidchain is free to move with said load carrier and said actuator sprocketis predisposed against rotation, and means whereby said chain is heldagainst motion as said carries. moves linearly whereupon said chain inturn rotates said actuator sprocket to rotate said carrier relatively toits mounting means as said load carrier moves linearly of said mainframe.

5. In a truck of the class described, a main frame, a load carrier,means mounting said load carrier for linear movement on said main frame,means mounting said load carrier for rotary movement relatively to saidmain frame, rotating wheels mounted on said main frame, an actuatorwheel fixed to said carrier with its axis coinciding with the axis ofrotation of said carrier for effecting rotation of said carrier on itsmounting means,

a flexible member reeved over all of said wheels, the linear motion ofsaid carrier and said actuator Wheel acting to move said flexible membertherewith relatively to the wheels on said main frame when said flexiblemember is free to move with said load carrier and said actuator Wheel ispredisposed against rotation, a brake for one of the rotating wheels onsaid main frame for holding said wheel against rotation and therebyholding said flexible member against motion whereupon said fiexiblemember in turn rotates said actuator wheel to rotate said carrierrelatively to its mounting means as said load carrier moves linearly ofsaid main frame.

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